package com.zy.explore.common.infrastructure.util;

import javax.servlet.http.HttpServletRequest;

/**
 * IP解析工具类
 *
 * @author ChinaYin  主页:https://gitee.com/zy-explorej2ee 邮箱:zyexplorej2ee@sina.com
 * @date 2021年06月13日 13:22:54
 */
public class IpUtil {

    public static String getIpAddress(HttpServletRequest request) {
        if (request == null) {
            return "localhost";
        }
        String ip = null;
        // X-Forwarded-For：Squid 服务代理
        String ipAddresses = request.getHeader("X-Forwarded-For");
        // Proxy-Client-IP：apache 服务代理
        String unknown = "unknown";
        if (ipAddresses == null || ipAddresses.length() == 0 || unknown.equalsIgnoreCase(ipAddresses)) {
            ipAddresses = request.getHeader("Proxy-Client-IP");
        }
        // WL-Proxy-Client-IP：weblogic 服务代理
        if (ipAddresses == null || ipAddresses.length() == 0 || unknown.equalsIgnoreCase(ipAddresses)) {
            ipAddresses = request.getHeader("WL-Proxy-Client-IP");
        }
        // HTTP_CLIENT_IP：有些代理服务器
        if (ipAddresses == null || ipAddresses.length() == 0 || unknown.equalsIgnoreCase(ipAddresses)) {
            ipAddresses = request.getHeader("HTTP_CLIENT_IP");
        }
        // X-Real-IP：nginx服务代理
        if (ipAddresses == null || ipAddresses.length() == 0 || unknown.equalsIgnoreCase(ipAddresses)) {
            ipAddresses = request.getHeader("X-Real-IP");
        }
        //有些网络通过多层代理，那么获取到的ip就会有多个，一般都是通过逗号（,）分割开来，并且第一个ip为客户端的真实IP
        if (ipAddresses != null && ipAddresses.length() != 0) {
            ip = ipAddresses.split(",")[0];
        }
        //还是不能获取到，最后再通过request.getRemoteAddr();获取
        if (ip == null || ip.length() == 0 || unknown.equalsIgnoreCase(ipAddresses)) {
            ip = request.getRemoteAddr();
        }
        return ip;
    }

}
